人間感染を引き起こす新型鳥インフルエンザA H7N9ウイルスの起源と多様性: 系統遺伝的,構造的,凝結分析
1CAS Key Laboratory of Pathogenic Microbiology and Immunology, Chinese Academy of Sciences, Beijing, China.
Lancet (London, England)
|May 7, 2013
まとめ
新型鳥インフルエンザA H7N9ウイルスは,少なくとも4つの源から発生した可能性があり,中介宿主としてアヒルや鶏が関与しています. この再分類により,異なるウイルスの系統が生み出され,鳥インフルエンザの世界的な監視を強化する必要が生まれました.
科学分野:
- ウイルス学 ウイルス学 ウイルス学
- ゲノミクスゲノミクスとは
- エピデミオロジー エピデミオロジー
背景:
- 2013年3月30日,中国でヒトに感染する新型鳥インフルエンザA H7N9ウイルスが確認されました.
- ウイルスは6つの州に急速に広がり,その起源に関する緊急の調査を促しました.
研究 の 目的:
- 新型鳥インフルエンザA H7N9ウイルスの起源と再分類イベントを調査する.
- ゲノムデータを生態学的情報と相関させ,系統遺伝学およびコアレスセント分析を行う.
主な方法:
- GISAID と Influenza Virus Resource から H7N9 ゲノム配列をダウンロードしました.
- ブートストラップ・レプリケートとベイジアン進化分析 (BEAST) を用いて系統樹を構築した.
- 人間の受容体結合に影響を与える突然変異を研究するために,配列アラインメントとホモロジーモデリングを使用した.
主要な成果:
- H7N9ウイルスは,アヒルおよび移動鳥の鳥インフルエンザウイルスに由来する遺伝子を持つ複数の再分類イベントの結果でした.
- 内部遺伝子は,おそらく2つの異なるH9N2鶏インフルエンザウイルス群から派生した.
- アヒルとニワトリは,おそらく中間宿主であると特定された; 単離体は2つの別々のサブクラードを形成した.
結論:
- H7N9ウイルスは,少なくとも4つの異なる起源から進化し,複雑な再分類を示しています.
- ウイルスの多様性は,少なくとも2つのH7N9系統の出現を示唆しています.
- 国内家禽から人間への感染のさらなる世界的な監視とモニタリングは極めて重要です.
さらに関連する動画
08:10Production of High-Titer Infectious Influenza Pseudotyped Particles with Envelope Glycoproteins from Highly Pathogenic H5N1 and Avian H7N9 Viruses
Published on: January 15, 2020
12:18Expression of Functional Recombinant Hemagglutinin and Neuraminidase Proteins from the Novel H7N9 Influenza Virus Using the Baculovirus Expression System
Published on: November 6, 2013
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